Adeney — Dissolved Gases and Fermentative Changes. 605 



BelatiousMp between the Oxygen consumed and the Nitrous Acid formed 

 during the Fermentation of Ammonia. 



The experiments which have just been considered show that, when the fermen- 

 tation of ammonia is carried on in the presence of peaty matters, the latter bodies 

 take part in the fermentation, and prevent the true relationship between the 

 oxygen consumed and the ammonia oxidized being seen. With the object of 

 obtaining exact experimental data as to this point, I commenced a further series 

 of experiments with a solution of ammonium chloride in distilled water, to which 

 a little potassium phosphate and sodium carbonate were added, but no organic 

 matter. 



Some five litres of this solution were seeded with a few drops of the mixed 

 sediments from the solution of peat (P/9), remaining in bottles II. and III. after 

 the conclusion of experiment 5, recorded in Table XIV. I hoped by this solution 

 to determine accurately the relation between the oxygen consumed and the 

 nitrous acid formed, during a purely nitrous fermentation, carried on in the 

 absence of peaty matters. 



At the same time, in order to be able to compare the results of this experiment 

 with those which would follow a fermentation by similar organisms in the 

 presence of peaty matters, I started two further experiments with portions of 

 the same peat solution remaining in the same bottles II. and III. To one portion 

 I added a known quantity of ammonium chloride ; to the other a known quantity 

 of potassium nitrite. I had a further object in commencing these experiments, 

 which I will describe later on. 



The details and results of these experiments are given in the subjoined 

 Table :— 



[Table XVI. 



4Q2 



